can you connect a wireless router to an internet cable only to get wifi on...

...a PS3 and blueray player? My son has internet service he connects to his PS3. Does not have a PC or laptop. I just bought him a blueray/DVD player with WiFi. Can he connect both with the internet cable or can he just connect the internet cable to a wireless router and use WiFi with both PS3 and the Blueray/DVD player and also use either as a computer? In other words, what does he need, instead of spending a lot of money on a PC or laptop, so he can use his tv as the monitor and the PS3 or bluesy as his computer?